Motor open-phase detection method, device and equipment and storage medium

Abstract

The invention relates to a motor open-phase detection method, device and equipment and a storage medium, and the method comprises the steps: calculating a deviation value between an expected operation current and an actual operation current of a motor in real time, judging whether the motor has a fault mark or not according to the deviation value and a preset error threshold value, and if the fault mark exists, determining that the motor is open-phase. And calculating the real-time current slope of the motor according to the actual operation current, and detecting whether the motor has an open-phase fault or not and / or detecting whether a frequency converter for controlling the motor has an output open-phase fault or not according to the interval of the real-time current slope of the motor. According to the invention, whether the motor has an open-phase fault or not and / or whether the frequency converter for controlling the motor has an output open-phase fault or not can be accurately detected.

Description

Technical Field

[0001] The present application relates to the technical field of motor detection, and in particular to a motor phase loss detection method, device, equipment and storage medium. Background Art

[0002] During the operation of the motor, the inverter may have a phase loss phenomenon due to factors such as motor winding failure, cable damage, and mechanical vibration. When a phase loss occurs in one phase of the motor, the current of the other two phases will increase sharply, resulting in serious current imbalance, which may exceed the rated current by many times. Phase loss will cause damage to the inverter on the one hand, and increase motor vibration on the other hand. Therefore, it is particularly important to detect the phase loss of the inverter output and / or the phase loss of the motor.

[0003] In the prior art, when detecting a phase loss fault in the inverter output or a phase loss in the motor, it is usually necessary to monitor whether the instantaneous value of the three-phase current is near 0 to determine whether there is a phase loss fault. However, in actual applications, this solution may not report a fault or may take a long time to determine the fault due to current glitches, resulting in inaccurate phase loss detection.

[0004] Therefore, how to accurately detect inverter output phase loss and / or motor phase loss has become a technical problem that needs to be solved urgently by those skilled in the art. Summary of the invention

[0005] In view of the above, the present application provides a motor phase loss detection method, device, equipment and storage medium, the purpose of which is to solve the above technical problems.

[0006] In a first aspect, the present application provides a method for detecting a phase loss in a motor, the method comprising:

[0007] Calculate the deviation between the expected motor operating current and the actual motor operating current in real time;

[0008] Determining whether the motor has a fault sign according to the deviation value and a preset error threshold value;

[0009] If a fault sign is present, calculating the real-time current slope of the motor according to the actual operating current;

[0010] According to the interval in which the real-time current slope of the motor is located, it is detected whether the motor has a phase loss fault and / or it is detected whether the frequency converter controlling the motor has an output phase loss fault.

[0011] In a second aspect, the present application provides a motor phase loss detection device, the device comprising:

[0012] The first calculation module is used to calculate the deviation value between the expected running current and the actual running current of the motor in real time;

[0013] A judgment module: used to judge whether the motor has a fault sign according to the deviation value and a preset error threshold value;

[0014] A second calculation module: used for calculating the real-time current slope of the motor according to the actual operating current if a fault sign exists;

[0015] Detection module: used to detect whether the motor has a phase loss fault and / or detect whether the inverter controlling the motor has an output phase loss fault according to the interval of the real-time current slope of the motor.

[0016] In a third aspect, the present application provides a motor phase loss detection device, including a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other via the communication bus;

[0017] Memory, used to store programs;

[0018] The processor is used to implement the motor phase loss detection method described in any embodiment of the first aspect when executing the program stored in the memory.

[0019] In a fourth aspect, a computer-readable storage medium is provided, on which a program is stored, and when the program is executed by a processor, the motor phase loss detection method as described in any embodiment of the first aspect is implemented.

[0020] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0021] This application calculates the deviation between the expected running current and the actual running current of the motor in real time, and determines whether the motor has a fault sign based on the deviation value and the preset error threshold value. If a fault sign exists, the real-time current slope of the motor is calculated based on the actual running current, which can ensure the same fault detection time at different speeds and avoid false alarms. Since the current slope will change periodically over time when the motor is operating normally in a healthy state, when a phase failure occurs in a certain phase of the motor, the current slope will maintain a fixed value. Therefore, based on the interval in which the real-time current slope of the motor is located, it is possible to accurately detect whether the motor has a phase failure and / or accurately detect whether the inverter that controls the motor has an output phase failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0023] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0024] Figure 1 This is a flow chart of an embodiment of a motor phase loss detection method of the present application;

[0025] Figure 2 This is a module schematic diagram of an embodiment of a motor phase loss detection device of the present application;

[0026] Figure 3 A schematic diagram of an embodiment of a motor phase loss detection device of the present application;

[0027] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0029] The disclosure below provides many different embodiments or examples to realize the different structures of the present application. In order to simplify the disclosure of the present application, the parts and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the present application. In addition, the present application can repeat reference numbers and / or letters in different examples. This repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed.

[0030] The present application provides a method for detecting a phase loss in a motor. Figure 1 , which is a schematic diagram of a method flow of an embodiment of a motor phase loss detection method of the present application. The method can be performed by a motor phase loss detection device, and the motor phase loss detection device can be implemented by software and / or hardware. The motor phase loss detection method includes:

[0031] Step S10: Calculate the deviation between the expected running current and the actual running current of the motor in real time;

[0032] Step S20: judging whether the motor has a fault sign according to the deviation value and a preset error threshold value;

[0033] Step S30: If a fault sign exists, calculating the real-time current slope of the motor according to the actual operating current;

[0034] Step S40: Detecting whether the motor has a phase loss fault and / or detecting whether the inverter controlling the motor has an output phase loss fault according to the interval in which the real-time current slope of the motor is located.

[0035] The solution of the present application is described in detail by taking the synchronous motor as a permanent magnet synchronous motor as an example. It should be noted that the solution of the present application can be applied to other types of synchronous motors such as induction synchronous motors, hybrid synchronous motors, and asynchronous motors, and the type of motor is not specifically limited here.

[0036] The expected operating current of the motor refers to the current during the healthy operation of the motor, which may also be referred to as the healthy operating current of the motor in this embodiment, including the expected D-axis current and the expected Q-axis current of the expected operating state. The expected operating current of the motor may be calculated by a pre-configured motor observation model, and the actual operating current refers to the current of the motor during actual operation, including the actual D-axis current and the actual Q-axis current of the actual operating state. Among them, the D-axis represents the direct-axis component of the motor magnetic field, and the Q-axis represents the quadrature-axis component of the motor magnetic field.

[0037] Since the healthy operating current of the motor is calculated in the DQ rotating coordinate system, the calculation will decouple the D-axis current and the Q-axis current, and whether the operating current is healthy needs to be measured by a unified error threshold. Therefore, in this embodiment, the sum of squared errors is used as an indicator of the deviation value to uniformly judge the current error to increase the fault tolerance of fault detection. It should be noted that the deviation value can also be an indicator of the deviation, such as mean square error, root mean square error, and mean absolute error. Specifically, the deviation value between the expected operating current and the actual operating current of the motor is calculated in real time, including:

[0038] Calculating in real time an expected D-axis current and an expected Q-axis current of the motor in an expected operating state according to a preconfigured motor observation model;

[0039] Obtaining an actual D-axis current and an actual Q-axis current of the motor in an actual operating state;

[0040] A deviation value between the expected operating current and the actual operating current of the motor is calculated according to the expected D-axis current, the expected Q-axis current, the actual D-axis current and the actual Q-axis current.

[0041] The pre-configured motor observation models are as follows:

[0042]

[0043] Among them, R sis the motor stator resistance, L d and L q are the D-axis inductance and Q-axis inductance of the motor stator, i dm and i qm are the expected D-axis current and expected Q-axis current in the motor DQ coordinate system, respectively, d * and u q * are the given values ​​of the motor stator D-axis voltage and Q-axis voltage, ω is the motor rotation angular velocity, ψ f is the permanent magnet flux of the motor.

[0044] The actual D-axis current and the actual Q-axis current of the motor in actual operation are obtained. Based on the expected D-axis current, the expected Q-axis current, the actual D-axis current and the actual Q-axis current, the square sum of the errors between the expected motor operation current and the actual motor operation current can be calculated. In order to avoid false alarms during normal operation of the motor, it is also necessary to perform a first-order low-pass filter on the deviation of the D-axis current and the deviation of the Q-axis current. The filter coefficient can be adjusted according to actual needs.

[0045] Further, the above step of “calculating the deviation value between the expected operating current and the actual operating current of the motor according to the expected D-axis current, the expected Q-axis current, the actual D-axis current and the actual Q-axis current” specifically includes:

[0046] Calculating a first difference between the expected D-axis current and the actual D-axis current, and performing a first-order low-pass filtering process on the first difference to obtain a filtered first difference;

[0047] Calculating a second difference between the expected Q-axis current and the actual Q-axis current, and performing a first-order low-pass filtering process on the second difference to obtain a filtered second difference;

[0048] The deviation value between the expected operating current and the actual operating current of the motor is calculated according to the filtered first difference and the filtered second difference.

[0049] Calculate the difference between the expected D-axis current and the actual D-axis current (recorded as the first difference x), and perform a first-order low-pass filter on the first difference to obtain the filtered first difference. Calculate the difference between the expected Q-axis current and the actual Q-axis current (recorded as the second difference y), and perform a first-order low-pass filter on the second difference to obtain the filtered second difference. The square sum of the error between the expected motor running current and the actual running current is expressed as: 2 +y 2 .

[0050] After obtaining the deviation value between the expected running current of the motor and the actual running current, determine whether the motor has a fault sign based on the size relationship between the deviation value and the preset error threshold value. For example, when the deviation value is greater than the preset error threshold value Current_Error_Th, it indicates that the motor may have a fault, so a fault sign can be generated. Since the deviation value may be greater than the error threshold value for a moment and then recover to be less than the error threshold, a false fault alarm may occur. For example, when a burr appears in the current, it is possible that the current error is greater than the error threshold value. Therefore, this embodiment avoids false alarms by adding a fault tolerance mechanism.

[0051] The following are specific steps of the fault tolerance mechanism, namely, the step of "judging whether the motor has a fault sign based on the deviation value and the preset error threshold value" includes:

[0052] Determine whether the deviation value is greater than the preset error threshold value;

[0053] If yes, control the first counter to start counting, and control the second counter to be cleared, wherein a fault flag is generated if the count value of the first counter reaches a first count threshold;

[0054] If not, the second counter is controlled to start counting, and the first counter is controlled to be cleared, wherein the fault flag is cleared if the count value of the second counter reaches a second count threshold.

[0055] Determine whether the deviation value is greater than the preset error threshold value. If it is greater than the error threshold value, no fault flag is generated first, but the first counter is controlled to start counting and the second counter is controlled to be cleared. The fault flag is generated when the first counter reaches the first counting threshold. The first counting threshold can be set according to actual needs. When a burr appears in the current, the deviation value is greater than the error threshold value. At this time, the first counter is controlled to count. Only when the count value of the first counter reaches the first counting threshold will the fault flag flag_start_detect be generated, and then the subsequent detection of whether the motor has a phase loss fault is performed. If the deviation value disappears within the first counting threshold, no fault flag will be generated, and no subsequent phase loss fault detection will be performed, thereby avoiding false alarms when the deviation value of a certain point is greater than the error threshold value for a moment and then returns to normal.

[0056] If the deviation value is less than or equal to the error threshold value, the second counter is controlled to start counting, and the first counter is controlled to be cleared, and the fault flag is cleared when the second counter reaches the second counting threshold. For example, at a certain moment, a current glitch occurs, causing the deviation value to be greater than the preset error threshold value, and a fault flag is generated. Since the subsequent detection of whether the motor has a phase failure also takes time, and the current fluctuation may reduce the deviation value to below the error threshold value, if the second counter is not added for counting, the previously generated fault flag will be immediately cleared, so that no fault will be reported. By adding the second counter for counting, the deviation value caused by the current fluctuation can be reduced for a short time, and the fault flag will not be cleared immediately. Only when the deviation value is reduced and the count of the second counter reaches the second counting threshold, the fault flag will be cleared, and the judgment of whether the motor is phase-deficient will be terminated. Therefore, adding two counters can increase the fault tolerance of the fault protection logic, and can prevent false faults due to large deviations in short-term current fluctuations, and prevent the situation where the fault is not reported when the deviation lasts for a long time.

[0057] If there is a fault flag, that is, when the fault flag flag_start_detect=1 is satisfied, the real-time current slope of the motor is calculated according to the actual running current. The real-time current slope can be the current vector circle slope. The actual sampled current of the motor can be converted into the current component of the stator current in the two-phase stationary αβ coordinate system, and the real-time current slope of the motor is calculated by current classification. Specifically, the above step of "calculating the real-time current slope of the motor according to the actual running current" includes:

[0058] Calculating the α-axis current component and the β-axis current component of the stator current of the motor in the αβ coordinate system according to the sampled current of the motor;

[0059] The ratio of the α-axis current component to the β-axis current component is calculated to obtain the real-time current slope of the motor.

[0060] After obtaining the α-axis current component and the β-axis current component of the motor's stator current in the αβ coordinate system, calculate the ratio of the α-axis current component to the β-axis current component, and use the ratio as the real-time current slope of the motor, expressed as:

[0061]

[0062] Where, k represents the real-time current slope, i α represents the α-axis current component, i β represents the β-axis current component.

[0063] After obtaining the real-time current slope of the motor, the real-time current slope can also be filtered to filter out the burr components in the real-time current slope. When the motor is running in a healthy state, the slope changes periodically over time. When a phase failure occurs in a certain phase of the motor, the current slope will maintain a fixed value. The specific value of this fixed value depends on which phase has the phase failure. Therefore, it is possible to detect whether the motor has a phase failure based on the interval of the real-time current slope after the motor is filtered.

[0064] Specifically, the above step of "detecting whether the motor has a phase loss fault and / or detecting whether the frequency converter controlling the motor has an output phase loss fault according to the interval in which the real-time current slope of the motor is located" includes:

[0065] If the real-time current slope is detected to be zero, a phase loss flag of phase a is generated;

[0066] If it is detected that the real-time current slope is in a preset interval, a phase loss flag of phase b is generated or a phase loss flag of phase c is generated;

[0067] When any phase-loss mark appears, the third counter is controlled to start counting;

[0068] If the third counter reaches a third counting threshold, it is determined that the motor has a phase loss fault and / or it is determined that the frequency converter controlling the motor has an output phase loss fault.

[0069] Combined with the following formula, the situation of detecting whether the motor has a phase failure is explained:

[0070]

[0071] Where k(k) represents the current slope value at the kth moment, k h is the slope error threshold, D a , D b , D c The above expressions mean that when the real-time current slope is within the slope error threshold, the corresponding phase loss flag will be set to 1. That is, when the real-time current slope remains at 0, it means that a phase loss fault has occurred in phase a, and the phase loss slope flag of phase a is set to 1. When phase b and phase c have phase loss faults, their real-time current slopes remain at and

[0072]

[0073] When any phase loss mark appears, the third counter is controlled to start counting. When the third counter reaches the third counting threshold, it is determined that the motor has a phase loss fault and / or that the inverter controlling the motor has an output phase loss fault, that is, the output motor is reported to have a phase loss fault when the following conditions are met:

[0074]

[0075] Among them, Fault a 、Fault b 、Fault c They are the phase failure signs of motor phase a, phase b and phase c respectively. a , D b , D c They are the phase loss slope flags of motor phases a, b, and c respectively, count1 represents the count of the third counter, and COUNT1 represents the third counting threshold. The phase loss slope flag is maintained for a period of time before reporting a motor defect fault, which increases the fault tolerance of phase loss fault detection. The target fault flag FaultFlag reported in the end is:

[0076] FaultFlag=Fault a +2*Fault b +3*Fault c

[0077] The specific fault phase of the motor can be determined based on the value of the target fault flag. FaultFlag=1 indicates a motor a phase fault, FaultFlag=2 indicates a motor b phase fault, and FaultFlag=3 indicates a motor c phase fault.

[0078] In one embodiment, after determining that the motor has a phase loss fault and / or determining that the frequency converter controlling the motor has an output phase loss fault, the method further includes:

[0079] The motor is controlled to stop running. When the motor has a phase failure, it may be caused by a fault in the motor itself, or it may be caused by a phase failure in the output of the inverter, which causes the motor to be phase-deficient when running. After detecting that the motor has a phase failure, the motor is controlled to stop running to protect the motor and the inverter in time.

[0080] Reference Figure 2 , which is a schematic diagram of the functional modules of the motor phase loss detection device 100 of the present application.

[0081] The motor phase loss detection device 100 described in the present application can be installed in a motor phase loss detection device. According to the functions to be implemented, the motor phase loss detection device 100 may include a first calculation module 110, a judgment module 120, a second calculation module 130 and a detection module 140. The module described in the present application may also be referred to as a unit, which refers to a series of program segments that can be executed by a processor of a motor phase loss detection device and can complete a fixed function.

[0082] In this embodiment, the functions of each module / unit are as follows:

[0083] The first calculation module 110 is used to calculate the deviation value between the expected running current and the actual running current of the motor in real time;

[0084] The judging module 120 is used to judge whether the motor has a fault sign according to the deviation value and the preset error threshold value;

[0085] The second calculation module 130 is used to calculate the real-time current slope of the motor according to the actual operating current if a fault sign exists;

[0086] The detection module 140 is used to detect whether the motor has a phase loss fault and / or detect whether the inverter controlling the motor has an output phase loss fault according to the interval where the real-time current slope of the motor is located.

[0087] In one embodiment, the real-time calculation of the deviation between the expected operating current and the actual operating current of the motor includes:

[0088] Calculating in real time an expected D-axis current and an expected Q-axis current of the motor in an expected operating state according to a preconfigured motor observation model;

[0089] Obtaining an actual D-axis current and an actual Q-axis current of the motor in an actual operating state;

[0090] A deviation value between the expected operating current and the actual operating current of the motor is calculated according to the expected D-axis current, the expected Q-axis current, the actual D-axis current and the actual Q-axis current.

[0091] In one embodiment, calculating the deviation value between the expected operating current and the actual operating current of the motor according to the expected D-axis current, the expected Q-axis current, the actual D-axis current, and the actual Q-axis current includes:

[0092] Calculating a first difference between the expected D-axis current and the actual D-axis current, and performing a first-order low-pass filtering process on the first difference to obtain a filtered first difference;

[0093] Calculating a second difference between the expected Q-axis current and the actual Q-axis current, and performing a first-order low-pass filtering process on the second difference to obtain a filtered second difference;

[0094] The deviation value between the expected operating current and the actual operating current of the motor is calculated according to the filtered first difference and the filtered second difference.

[0095] In one embodiment, judging whether the motor has a fault sign according to the deviation value and the preset error threshold value includes:

[0096] Determine whether the deviation value is greater than the preset error threshold value;

[0097] If yes, control the first counter to start counting, and control the second counter to be cleared, wherein a fault flag is generated if the count value of the first counter reaches a first count threshold;

[0098] If not, the second counter is controlled to start counting, and the first counter is controlled to be cleared, wherein the fault flag is cleared if the count value of the second counter reaches a second count threshold.

[0099] In one embodiment, calculating the real-time current slope of the motor according to the actual operating current includes:

[0100] Calculating the α-axis current component and the β-axis current component of the stator current of the motor in the αβ coordinate system according to the sampled current of the motor;

[0101] The ratio of the α-axis current component to the β-axis current component is calculated to obtain the real-time current slope of the motor.

[0102] In one embodiment, detecting whether the motor has a phase loss fault and / or detecting whether the frequency converter controlling the motor has an output phase loss fault according to the interval in which the real-time current slope of the motor is located includes:

[0103] If the real-time current slope is detected to be zero, a phase loss flag of phase a is generated;

[0104] If it is detected that the real-time current slope is in a preset interval, a phase loss flag of phase b is generated or a phase loss flag of phase c is generated;

[0105] When any phase-loss mark appears, the third counter is controlled to start counting;

[0106] If the third counter reaches a third counting threshold, it is determined that the motor has a phase loss fault and / or it is determined that the frequency converter controlling the motor has an output phase loss fault.

[0107] In one embodiment, the motor phase failure detection device further includes a control module, and the control module is used to control the motor to stop running.

[0108] Reference Figure 3 As shown, it is a schematic diagram of a preferred embodiment of the motor phase loss detection device of the present application.

[0109] The motor phase loss detection device includes a processor 111, a communication interface 112, a memory 113 and a communication bus 114, wherein the processor 111, the communication interface 112, and the memory 113 communicate with each other through the communication bus 114;

[0110] A memory 113, used for storing programs;

[0111] Figure 3 Only a motor phase loss detection device having components 111 - 114 is shown, but it should be understood that it is not required to implement all of the components shown, and more or fewer components may be implemented instead.

[0112] In one embodiment of the present application, the processor 111 is used to execute the program stored in the memory 113 to implement the motor phase loss detection method provided by any of the above method embodiments, including:

[0113] Calculate the deviation between the expected motor operating current and the actual motor operating current in real time;

[0114] Determining whether the motor has a fault sign according to the deviation value and a preset error threshold value;

[0115] If a fault sign is present, calculating the real-time current slope of the motor according to the actual operating current;

[0116] According to the interval in which the real-time current slope of the motor is located, it is detected whether the motor has a phase loss fault and / or it is detected whether the frequency converter controlling the motor has an output phase loss fault.

[0117] For a detailed description of the above steps, please refer to the above Figure 1 Description of a flowchart of an embodiment of a method for detecting a phase loss in a motor.

[0118] In addition, the embodiment of the present application also proposes a computer-readable storage medium, which can be non-volatile or volatile. The computer-readable storage medium includes a data storage area and a program storage area, and the program storage area stores a motor phase loss detection program. When the motor phase loss detection program is executed by the processor, the following operations are implemented:

[0119] Calculate the deviation between the expected motor operating current and the actual motor operating current in real time;

[0120] Determining whether the motor has a fault sign according to the deviation value and a preset error threshold value;

[0121] If a fault sign is present, calculating the real-time current slope of the motor according to the actual operating current;

[0122] According to the interval in which the real-time current slope of the motor is located, it is detected whether the motor has a phase loss fault and / or it is detected whether the frequency converter controlling the motor has an output phase loss fault.

[0123] The specific implementation of the computer-readable storage medium of the present application is substantially the same as the specific implementation of the above-mentioned motor phase loss detection method, and will not be described in detail here.

[0124] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0125] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a general hardware platform, and of course, by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the relevant technology can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0126] It should be noted that the descriptions involving "first", "second", etc. in this application are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0127] It should be understood that the terms used herein are only for the purpose of describing specific example embodiments and are not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms "one", "an" and "said" as used herein may also be meant to include plural forms. The terms "include", "comprise", "contain", and "have" are inclusive, and therefore specify the existence of stated features, steps, operations, elements and / or parts, but do not exclude the existence or addition of one or more other features, steps, operations, elements, parts, and / or combinations thereof. The method steps, processes, and operations described herein are not interpreted as necessarily requiring them to be performed in the specific order described or illustrated, unless the execution order is clearly indicated. It should also be understood that additional or alternative steps may be used.

[0128] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A method for detecting a motor phase loss, characterized in that: The method comprises: Calculate the deviation between the expected motor operating current and the actual motor operating current in real time; Determining whether the motor has a fault sign according to the deviation value and a preset error threshold value; If a fault sign is present, calculating the real-time current slope of the motor according to the actual operating current; According to the interval in which the real-time current slope of the motor is located, it is detected whether the motor has a phase loss fault and / or it is detected whether the frequency converter controlling the motor has an output phase loss fault.

2. The motor phase loss detection method according to claim 1, characterized in that: The real-time calculation of the deviation value between the expected running current and the actual running current of the motor includes: Calculating in real time an expected D-axis current and an expected Q-axis current of the motor in an expected operating state according to a preconfigured motor observation model; Obtaining an actual D-axis current and an actual Q-axis current of the motor in an actual operating state; A deviation value between the expected operating current and the actual operating current of the motor is calculated according to the expected D-axis current, the expected Q-axis current, the actual D-axis current and the actual Q-axis current.

3. The motor phase loss detection method according to claim 2, characterized in that: The calculating, according to the expected D-axis current, the expected Q-axis current, the actual D-axis current and the actual Q-axis current, a deviation value between the expected motor operating current and the actual operating current includes: Calculating a first difference between the expected D-axis current and the actual D-axis current, and performing a first-order low-pass filtering process on the first difference to obtain a filtered first difference; Calculating a second difference between the expected Q-axis current and the actual Q-axis current, and performing a first-order low-pass filtering process on the second difference to obtain a filtered second difference; The deviation value between the expected operating current and the actual operating current of the motor is calculated according to the filtered first difference and the filtered second difference.

4. The motor phase loss detection method according to claim 1, characterized in that: The determining, based on the deviation value and the preset error threshold value, whether the motor has a fault sign includes: Determine whether the deviation value is greater than the preset error threshold value; If yes, control the first counter to start counting, and control the second counter to be cleared, wherein a fault flag is generated if the count value of the first counter reaches a first count threshold; If not, the second counter is controlled to start counting, and the first counter is controlled to be cleared, wherein the fault flag is cleared if the count value of the second counter reaches a second count threshold.

5. The motor phase loss detection method according to claim 1, characterized in that: Calculating the real-time current slope of the motor according to the actual operating current includes: Calculating the α-axis current component and the β-axis current component of the stator current of the motor in the αβ coordinate system according to the sampled current of the motor; The ratio of the α-axis current component to the β-axis current component is calculated to obtain the real-time current slope of the motor.

6. The motor phase loss detection method according to claim 1, characterized in that: The detecting, according to the interval in which the real-time current slope of the motor is located, whether the motor has a phase loss fault and / or detecting whether the frequency converter controlling the motor has an output phase loss fault comprises: If the real-time current slope is detected to be zero, a phase loss flag of phase a is generated; If it is detected that the real-time current slope is in a preset interval, a phase loss flag of phase b is generated or a phase loss flag of phase c is generated; When any phase-loss mark appears, the third counter is controlled to start counting; If the third counter reaches a third counting threshold, it is determined that the motor has a phase loss fault and / or it is determined that the frequency converter controlling the motor has an output phase loss fault.

7. The motor phase loss detection method according to claim 6, characterized in that: After determining that the motor has a phase loss fault and / or determining that the frequency converter controlling the motor has an output phase loss fault, the method further includes: The motor is controlled to stop running.

8. A motor phase loss detection device, characterized in that: The device comprises: The first calculation module is used to calculate the deviation value between the expected running current and the actual running current of the motor in real time; A judgment module: used to judge whether the motor has a fault sign according to the deviation value and a preset error threshold value; A second calculation module: used for calculating the real-time current slope of the motor according to the actual operating current if a fault sign exists; Detection module: used to detect whether the motor has a phase loss fault and / or detect whether the inverter controlling the motor has an output phase loss fault according to the interval of the real-time current slope of the motor.

9. A motor phase loss detection device, characterized in that: It includes a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other through the communication bus; Memory, used to store programs; The processor is used to implement the motor phase loss detection method described in any one of claims 1 to 7 when executing the program stored in the memory.

10. A computer-readable storage medium having a program stored thereon, characterized in that: When the program is executed by a processor, the motor phase loss detection method according to any one of claims 1 to 7 is implemented.

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